/src/middleware/lua/lundump.c

  1/*
  2** $Id: lundump.c,v 2.7.1.4 2008/04/04 19:51:41 roberto Exp $
  3** load precompiled Lua chunks
  4** See Copyright Notice in lua.h
  5*/
  6
  7#include <string.h>
  8
  9#define lundump_c
 10#define LUA_CORE
 11
 12#include "lua.h"
 13
 14#include "ldebug.h"
 15#include "ldo.h"
 16#include "lfunc.h"
 17#include "lmem.h"
 18#include "lobject.h"
 19#include "lstring.h"
 20#include "lundump.h"
 21#include "lzio.h"
 22
 23typedef struct {
 24 lua_State* L;
 25 ZIO* Z;
 26 Mbuffer* b;
 27 const char* name;
 28} LoadState;
 29
 30#ifdef LUAC_TRUST_BINARIES
 31#define IF(c,s)
 32#define error(S,s)
 33#else
 34#define IF(c,s)		if (c) error(S,s)
 35
 36static void error(LoadState* S, const char* why)
 37{
 38 luaO_pushfstring(S->L,"%s: %s in precompiled chunk",S->name,why);
 39 luaD_throw(S->L,LUA_ERRSYNTAX);
 40}
 41#endif
 42
 43#define LoadMem(S,b,n,size)	LoadBlock(S,b,(n)*(size))
 44#define	LoadByte(S)		(lu_byte)LoadChar(S)
 45#define LoadVar(S,x)		LoadMem(S,&x,1,sizeof(x))
 46#define LoadVector(S,b,n,size)	LoadMem(S,b,n,size)
 47
 48static void LoadBlock(LoadState* S, void* b, size_t size)
 49{
 50 size_t r=luaZ_read(S->Z,b,size);
 51 IF (r!=0, "unexpected end");
 52}
 53
 54static int LoadChar(LoadState* S)
 55{
 56 char x;
 57 LoadVar(S,x);
 58 return x;
 59}
 60
 61static int LoadInt(LoadState* S)
 62{
 63 int x;
 64 LoadVar(S,x);
 65 IF (x<0, "bad integer");
 66 return x;
 67}
 68
 69static lua_Number LoadNumber(LoadState* S)
 70{
 71 lua_Number x;
 72 LoadVar(S,x);
 73 return x;
 74}
 75
 76static TString* LoadString(LoadState* S)
 77{
 78 size_t size;
 79 LoadVar(S,size);
 80 if (size==0)
 81  return NULL;
 82 else
 83 {
 84  char* s=luaZ_openspace(S->L,S->b,size);
 85  LoadBlock(S,s,size);
 86  return luaS_newlstr(S->L,s,size-1);		/* remove trailing '\0' */
 87 }
 88}
 89
 90static void LoadCode(LoadState* S, Proto* f)
 91{
 92 int n=LoadInt(S);
 93 f->code=luaM_newvector(S->L,n,Instruction);
 94 f->sizecode=n;
 95 LoadVector(S,f->code,n,sizeof(Instruction));
 96}
 97
 98static Proto* LoadFunction(LoadState* S, TString* p);
 99
100static void LoadConstants(LoadState* S, Proto* f)
101{
102 int i,n;
103 n=LoadInt(S);
104 f->k=luaM_newvector(S->L,n,TValue);
105 f->sizek=n;
106 for (i=0; i<n; i++) setnilvalue(&f->k[i]);
107 for (i=0; i<n; i++)
108 {
109  TValue* o=&f->k[i];
110  int t=LoadChar(S);
111  switch (t)
112  {
113   case LUA_TNIL:
114   	setnilvalue(o);
115	break;
116   case LUA_TBOOLEAN:
117   	setbvalue(o,LoadChar(S)!=0);
118	break;
119   case LUA_TNUMBER:
120	setnvalue(o,LoadNumber(S));
121	break;
122   case LUA_TSTRING:
123	setsvalue2n(S->L,o,LoadString(S));
124	break;
125   default:
126	error(S,"bad constant");
127	break;
128  }
129 }
130 n=LoadInt(S);
131 f->p=luaM_newvector(S->L,n,Proto*);
132 f->sizep=n;
133 for (i=0; i<n; i++) f->p[i]=NULL;
134 for (i=0; i<n; i++) f->p[i]=LoadFunction(S,f->source);
135}
136
137static void LoadDebug(LoadState* S, Proto* f)
138{
139 int i,n;
140 n=LoadInt(S);
141 f->lineinfo=luaM_newvector(S->L,n,int);
142 f->sizelineinfo=n;
143 LoadVector(S,f->lineinfo,n,sizeof(int));
144 n=LoadInt(S);
145 f->locvars=luaM_newvector(S->L,n,LocVar);
146 f->sizelocvars=n;
147 for (i=0; i<n; i++) f->locvars[i].varname=NULL;
148 for (i=0; i<n; i++)
149 {
150  f->locvars[i].varname=LoadString(S);
151  f->locvars[i].startpc=LoadInt(S);
152  f->locvars[i].endpc=LoadInt(S);
153 }
154 n=LoadInt(S);
155 f->upvalues=luaM_newvector(S->L,n,TString*);
156 f->sizeupvalues=n;
157 for (i=0; i<n; i++) f->upvalues[i]=NULL;
158 for (i=0; i<n; i++) f->upvalues[i]=LoadString(S);
159}
160
161static Proto* LoadFunction(LoadState* S, TString* p)
162{
163 Proto* f;
164 if (++S->L->nCcalls > LUAI_MAXCCALLS) error(S,"code too deep");
165 f=luaF_newproto(S->L);
166 setptvalue2s(S->L,S->L->top,f); incr_top(S->L);
167 f->source=LoadString(S); if (f->source==NULL) f->source=p;
168 f->linedefined=LoadInt(S);
169 f->lastlinedefined=LoadInt(S);
170 f->nups=LoadByte(S);
171 f->numparams=LoadByte(S);
172 f->is_vararg=LoadByte(S);
173 f->maxstacksize=LoadByte(S);
174 LoadCode(S,f);
175 LoadConstants(S,f);
176 LoadDebug(S,f);
177 IF (!luaG_checkcode(f), "bad code");
178 S->L->top--;
179 S->L->nCcalls--;
180 return f;
181}
182
183static void LoadHeader(LoadState* S)
184{
185 char h[LUAC_HEADERSIZE];
186 char s[LUAC_HEADERSIZE];
187 luaU_header(h);
188 LoadBlock(S,s,LUAC_HEADERSIZE);
189 IF (memcmp(h,s,LUAC_HEADERSIZE)!=0, "bad header");
190}
191
192/*
193** load precompiled chunk
194*/
195Proto* luaU_undump (lua_State* L, ZIO* Z, Mbuffer* buff, const char* name)
196{
197 LoadState S;
198 if (*name=='@' || *name=='=')
199  S.name=name+1;
200 else if (*name==LUA_SIGNATURE[0])
201  S.name="binary string";
202 else
203  S.name=name;
204 S.L=L;
205 S.Z=Z;
206 S.b=buff;
207 LoadHeader(&S);
208 return LoadFunction(&S,luaS_newliteral(L,"=?"));
209}
210
211/*
212* make header
213*/
214void luaU_header (char* h)
215{
216 int x=1;
217 memcpy(h,LUA_SIGNATURE,sizeof(LUA_SIGNATURE)-1);
218 h+=sizeof(LUA_SIGNATURE)-1;
219 *h++=(char)LUAC_VERSION;
220 *h++=(char)LUAC_FORMAT;
221 *h++=(char)*(char*)&x;				/* endianness */
222 *h++=(char)sizeof(int);
223 *h++=(char)sizeof(size_t);
224 *h++=(char)sizeof(Instruction);
225 *h++=(char)sizeof(lua_Number);
226 *h++=(char)(((lua_Number)0.5)==0);		/* is lua_Number integral? */
227}